The Internet's big upgrade, Internet Protocol version 6 (IPv6), has big advantages but it is being held up through cost concerns, consulting firm INS has revealed [pdf].

IT professionals are interested in the additional authentication and security services built into IPv6, but few are committed to migrating because of a lack in measurable return on investment. INS surveyed over 200 IT professionals to reach its conclusions.

IPv6 was created a decade ago by the IETF to ward off an anticipated address space crunch with IPv4, the Internet’s current protocol. IPv6 uses a 128-bit addressing scheme and so can support vastly more unique Internet addresses.

But it is the other features of IPv6 - built-in security via IPSec, easier administration and improved quality of service - that are getting more interest at the moment. Indeed, one of the reasons IPv6 has been slow to catch on in the United States is that IPv4 address space is still widely available.

In the survey, 56 percent of respondents said they considered IPv6's authentication and security services "very important", with more than 90 percent giving it very important or somewhat important status. More than 90 percent also ranked the quality of service benefits as very important or somewhat important.

The other features of IPv6 - more efficient packet routing, expanded address space, auto-configuration, simplified headers and flow labels - were rated less important. However, they still received a very important or somewhat important ranking by more than 70 percent of respondents.

But few have committed to migrating to the new protocol. Only two percent of respondents have migrated to IPv6 across their organisations while 11 percent are in the process of migrating or will migrate within the next 12 months.

Of the remaining respondents, 39 percent have assessed the benefits of IPv6 but have not begun migration, 13 percent have decided not to migrate within the next two years and 8 percent will not start migrating in the next three years. More than a quarter of the respondents have not even considered IPv6.

What’s holding IT shops back from migrating to IPv6 is a lack of return on investment, the survey found. Most respondents - 70 percent - agree that IPv6 is a mature enough technology to deploy with confidence. However, 71 percent of respondents say there is not a strong enough ROI to deploy IPv6. Similarly, 58 percent of respondents say that it has value but does not link to business drivers.

"This combo [weak ROI and business-driver link] is likely to be, more than anything else, the key factors behind the slow adoption curve for IPv6," INS says.

The survey found that the biggest hurdles to IPv6 deployment continue to be the complexity of an infrastructure upgrade and the concern about converting existing applications and middleware. Equipment costs are also a barrier, as is the perception that the only benefit of IPv6 is expanded address space. Retraining and network management headaches were of little concern to respondents.